Domestic security investigations are primarily concerned with acts of domestic terrorism--that is, with unlawful past current, or planned acts of politically or socially motivated violence in the United States. These investigations seek domestic intelligence, information that will lead to the conviction and punishment of the perpetrators of past acts of terrorist violence, ameliorate the consequences of current acts, and forestall the commission of planned acts. Virtually every aspect of domestic security investigations is constrained by rules, which are continually changing, generally in the direction of increased hindrances. This Note presents a survey of readily available source materials dealing with constraints of the 1970s on the collection, maintenance, use, and dissemination of domestic intelligence. It describes legal, legislative, and administrative constraints that arose or were modified during the 1970s, a decade of particularly marked changes. It does not examine the recent changes made by the Reagan Administration.